Youth typically do not seek mental health services for themselves, and instead rely on their parents to play a “gatekeeper role,” and identify the problem and seek appropriate services for the youth. Youth Mental Health First Aid (YMHFA) USA teaches adults to recognize signs of youth mental illness and intervene using a five-step action plan that focuses on assessing for risk, listening nonjudgmentally, and connecting youth to resources and mental health care. While studies have examined the effects of the program on various stakeholders in children’s lives, limited attention has been given to parent trainees. The present study examined the effects of YMHFA USA on parents’ mental health literacy; mental health first aid intentions, self-reported MHFA behaviors to help youth, and confidence in their helping skills; attitudes toward seeking professional help and intentions to do so; and stigma. Six trainings were provided at no cost to parents with at least one child under the age of 21, and 107 parents participated in the research by completing pre-, post-, and two month follow-up surveys (n = 64). Paired sample t-tests were conducted to examine change, and results indicated that following the training, parents reported statistically significant increases in all variables of interest with the exception of stigma, which decreased. Changes in MHL, attitudes, intentions toward help-seeking, and stigma were maintained at two month follow-up. Participants answered six open-ended questions and responses were thematically analyzed. Qualitative results indicate that parents signed up for YMHFA USA due to a desire for knowledge and skills, having multiple roles that necessitate interactions with youth, prior experience with mental illness, and the increasing prevalence of youth mental illness. Parents identified that the most beneficial aspects of the training were learning the ALGEE action plan, participating in roleplays and examples, gaining information about youth mental illness, having a positive/open training environment, and learning strategies for understanding and interacting with youth. Finally, improvements to YMHFA USA were suggested in regard to both the content and structure of the training. Implications for practice and research are discussed.